Question

Optical fibers are generally composed of silica, with an index of refraction around 1.44. How fast does light travel in a silica fiber?

Answer 1

Given :

▪ Refractive index of silica = 1.44

To Find :

▪ Speed of ligh in silica fibre.

Concept :

→ Refractive index of a medium is defined as the factor by which speed of light reduces as compared to the speed of light in vacuum.

$\bigstar\:\underline{\boxed{\bf{\pink{n=\dfrac{c}{v}=\dfrac{speed\:of\:light\:in\:vacuum}{speed\:of\:light\:in\:medium}}}}}$

→ More (less) refractive index implies less (more) speed of light in that medium, which therefore is called denser (rarer) medium.

Calculation :

$\dashrightarrow\sf\:n=\dfrac{c}{v}\\ \\ \dashrightarrow\sf\:1.44=\dfrac{3\times 10^8}{v}\\ \\ \dashrightarrow\sf\:v=\dfrac{3\times 10^8}{1.44}\\ \\ \dashrightarrow\underline{\boxed{\bf{\purple{v=2.08\times 10^8\:mps}}}}\:\orange{\bigstar}$

Answer 2

Answer:

Light travel in a silica fiber with a speed of 2.08 x 10^8 m/s.

Explanation:

Given

Refractive index of silica = 1.44

we need to find the speed of light travel in silica fiber.

Refractive index of a medium:

• Refractive index is a measure of how light travels through a medium.
• It is a value calculated from the ratio of the speed of light in a vacuum to the second medium of greater density.
• The higher the refractive index the slower light travels.  
• It is denoted by the alphabet 'n'.
• The formula for refractive index is

                   n = c/v

             where n is the refractive index of medium

                         c is the speed of light in vacuum = 3x 10^8 m/s

                         v is the speed of light in medium

here the medium is silica and the refractive index of silica n = 1.44

             now we can write speed of light in silica(v) as

                      v = c/n

                      v = (3x10^8)/ 1.44

                      v = 2.08 x 10^8 m/s

Hence the speed of light travel in a silica fiber = 2.08 x 10^8m/s

Know more about Refractive index:

https://brainly.in/question/51328?referrer=searchResults